1. Field
The present invention relates to a fan duct device, and more particularly to a fan duct device for guiding airflow to improve air convection of a heat dissipation device installed within a computer enclosure, wherein a length of the fan duct device is adjustable so that position of a fan mounted on the fan duct can be easily altered.
2. Related Art
In the art of heat management, a heat sink having a fan mounted thereon is frequently employed. Commonly, a heat sink comprises a base for absorbing heat from a heat-generating component and a plurality of fins extending from the base to dissipate heat to an ambient environment. Channels are defined between adjacent fins of the heat sink for flow of air. The fan is mounted to a top or a side of the heat sink to enhance air convection in the channels. However, the heat sink and the fan are usually positioned in an enclosure in which the heat-generating component is set. Whether the fan is used to blow air to the heat sink or to draw heated air away from the heat sink, the air passing through and heated by the heat sink is subject to mixture with fresh air and enter the heat sink again. This adversely degrades the heat discharge ability of the heat sink.
To overcome the foregoing disadvantage of the heat sink/fan combination, a fan duct device has been developed. An end of the fan duct device is mounted with a fan. An opposite end of the fan duct device is engaged with an enclosure of a computer and communicates with an exterior of the enclosure. During operation of the fan, fresh air can be directly drawn into the heat sink from an exterior of the enclosure through the fan duct device when the fan is used to blow air to the heat sink, or the air passing through and heated by the heat sink can be directly discharged to the exterior of the enclosure through the fan duct device when the fan is used to draw heated air away from the heat sink. Therefore, by the use of the fan duct device, the heated air will not mix with the fresh air and flow again toward the heat sink. As a result, a better heat-dissipation efficiency can be achieved.
Unfortunately, the fan duct generally has a fixed configuration and dimension, whereas specification of the enclosure is varied. Consequently, the fan duct device cannot be adjusted to meet an enclosure with a different specification.